Of fictitious machine tool build model and treatment process to emulate

Fictitious machine tool of VMT(Virtual Machine Tool) of fictitious machine tool is to point to numerical control machine tool (be like machining center) the map below fictitious environment. For pursuit " be personally on the scene " distinct sex and " surmount reality " fictitious sex, fictitious machine tool should satisfy following requirements: The comprehensive, treatment environment that reflects reality realistically and treatment process; Can offer to the collision that appears in treatment, interference call the police information; Can undertake assessment to the rationality of the machinability of the product and procedure; Can undertake assessment to the treatment precision of the product, forecast; Must have processing a variety of products and the ability of a variety of treatment craft. Fictitious machine tool is main by treatment process of environmental model, treatment process model, treatment emulates interface of model, fictitious operation and graph to handle module to form. The three-dimensional geometry model that treatment environment model includes model of product of semifinished product, metaphase, end product model, cutting tool, clamping apparatus, machine tool to make resource and environmental content wait for all sorts of hypostatic objects with etc reachs the relation between the model. The heat in machining process model to include the cutting course of all sorts of treatment method correspondence is out of shape, suffer force to be out of shape reach oscillatory model. Graph 1 4 coordinate are fictitious machine tool 2.

Of fictitious treatment process build a model 2. 1 fictitious machine tool builds a model the carrier that fictitious machine tool is fictitious treatment process and core, form by geometrical model and athletic model. If pursue 1 be machining center of 14 coordinate horizontal simplify geometrical model. Fictitious machine tool is medium in the graph having two coordinate is, a X of world coordinate system that is a machine tool ' Y ' Z ' , another graph that is fictitious environment shows coordinate fastens XYZ. Because the cutting tool of machining center changes knife position,be fixed, the origin that reason fastens machine tool coordinate is changing the center of knife position surely. The origin that fastens graphical coordinate is in the center of workbench installed surface surely. Component of a motion in fictitious machine tool is corresponding a coordinate, if the graph is shown 1 times, workbench, component 1, 2, 3 part corresponding at coordinate B, X, Z, Y. Each motion component and lathe bed make one kinematic chain by definite pattern, stipulate kinematic chain is initiative at workbench, stop at machine tool main shaft, if pursue,2 are shown. The existence between component of adjacent of the photograph in kinematic chain contacts a relation, lathe bed is do not move, for bound general kinematic chain with its cent is two paragraphs, each paragraphs all have hierarchy. Namely every paragraphs in when the person that leave lathe bed close moves, the person that leave lathe bed far all will subsequently and move. When like the component coordinate of 2 edges Z moves, workbench and component 1 will move along Z coordinate subsequently; And component when coordinate of 3 edges Y moves, main shaft general subsequently and move. The virtual campaign of fictitious machine tool is reached by the translation of each motion component, roll mutual the linkage between is formed. The linkage of many motion component uses interpolation algorithm but the translation of component of motion of translate into sheet or roll. Accordingly, the motion of fictitious machine tool can rotate through undertaking to the component translation is mixed change will come true. Virtual campaign speed is controlled by translation and gyral step pitch value. Of athletic process build a model to use object-oriented virtual reality to build modular language VRML to finish. Specific for use VRML language to be definition of each motion component object of a motion, such each motion objects can regard a node as in VRML language, a node includes a group of episode that it can be accepted and send, if change the position (translation or rotate) wait with the incident that changes color. The each setting that machines a process can be defined for a group of node, whole treatment process is the gather of a series of setting. Graph kinematic chain of 2 fictitious machine tools pursues 3 empty body builds a model 2. The model of process of the treatment that build a model of 2 treatment process shows all at representing product behavior and the physical model of production process using, the heat in including all sorts of cutting courses that machine methodological correspondence is out of shape, cutting strength effect issues systematic tigidity to be out of shape, clamp is out of shape etc. Machining process model is the main basis that evaluate and forecasts a product to machine precision and machinability, their build with condition of treatment method, cutting (material of appearance of cutting tool structure, cutting tool, workpiece material) wait with cutting dosage about. Specific mathematical model can pass a test or finite yuan the analysis builds a model to build about. 2. 3 emulation processes build a model the treatment in fictitious machine tool is dictated by NC motion of control cutting tool is finished, in the process that implements directive of each paragraphs of NC, cutting tool moves via some method from some position of rest another position. The process is here medium, cutting tool had swept certain volume in the space, what the dimensional body of subsidiary channels in the human body through which vital energy says can include cutting tool to be in athletic process " empty body " (Swept Volume Solid) . If the graph is shown 3 times, the columnar milling cutter in graph 3a (cutting blade part) the empty body that if graph 3b place is shown,forms. As opposite as actual form and structure and character, it is not actual form and structure, but when be being calculated and building a model, can come to it handle as actual form and structure. The contrail that the geometrical appearance of empty body and cutting tool itself, cutting tool moves and the position of rest that cutting tool moves are having inseparable connection. Because empty body is object of You Jing condition,form in athletic process, can use static object (cutting tool) the method that attrib border curved surface forms the surface that include sth resembling a net in motion undertakes building a model to empty body. Have empty body and body of other static state begging making operation, can check the collision in machining a process and interference; And have semifinished product and empty body begging needing operation, can emulate the purify process of material. Accordingly, adopt pair of empty form and structure build a model, can realize the emulation to machining a process. 3.

Fictitious treatment process is emulated 3.

Of 1 emulation environment build build emulation environment to basically include to define library of fictitious machine tool, knife and cutting tool, clamping device, semifinished product and workpiece. Definition knife library includes to press treatment order make choice of every cutting tool, define cutting tool parameter. Define fictitious machine tool to include to ask to fix system of number of machine tool type, coordinate, control according to treatment, origin of machine tool coordinate, graphical coordinate origin and process designing origin. The origin that fastens with graphical coordinate below default condition is process designing origin. The origin jackknife that clamping apparatus, semifinished product and workpiece can carry the origin that fastens product coordinate and graphical coordinate department in the initiative installation on workbench will come true, actual installation position can pass origin of coordinate of opposite to the product graph to undertake translation commutation gets. Department of the coordinate when the product builds a model is fixed commonly, and to different machine tool its coordinate department is different, because this should be in on workbench when clamping device or semifinished product, its fasten medium position to decide by the commutation of the coordinate that be as follows in graphical coordinate: (X, y, z, 1)=A*B*(x1, y1, z1, in 1) type (X1, y1, z1) is fastened for product coordinate a bit medium, (X, y, z) fastens the relevant point below for coordinate of the graph in fictitious environment. A11~a33 passes the some coordinate side that chooses product coordinate department, be like XOY, XO-Y, XOZ, - XOZ, YOZ, - one of YOZ, the jackknife of face of XOY of coordinate tool reference plane that fastens with graphical coordinate will decide. (X0, y0, z0) is the center of workbench installed surface to tie medium coordinate cost in machine tool coordinate. 3.

2 treatment process emulates the emulation of treatment process to use 3 kinds of forms: Contrail of cutting tool motion is emulated, it is cutting tool moves around semifinished product by treatment contrail only right now, the purpose is intuitionistic examine the rationality of contrail of cutting tool motion. Process of machine tool campaign is emulated, get on workpiece installation in machine tool workbench right now, athletic contrail decomposes cutting tool to move each for the machine tool the motion of the component, the purpose is intuitionistic examine the collision between cutting tool and machine tool component and machine tool component and interference. Material purify process is emulated, right now cutting tool undertakes to semifinished product by its motion contrail material is excised, the purpose is the cutting process with actual imitate, generate a product to machine result model, undertake assessment to machining precision and machinability. In emulating a process here, pass estimation cutting force, clamping force and heat in metal cutting, be out of shape machining complex because of heat and suffer force to be out of shape the theory of the opposite displacement between the cutting tool that cause and workpiece and cutting tool moves orbit overlay, the model of product treatment result that makes generate can reflect dynamic factor the influence to machining quality. 3.

The treatment result model that the assessment of 3 machining error will get after the theoretical model of product part and material of semifinished product purify begs difference, model of attainable machining error. In machining error model, those who machine area to press error size is different express with different color, through having visual check to its, the reason that can reach its to arise to the size of machining error has analysis, judgement, the machinability that is a product is evaluated provide a basis. 4.

Fictitious machine tool is conclusion to did not build fictitious production system lay a foundation not only, and positive effect can produce in the following respects: Groom personnel of NC code process designing and; of type selecting of equipment of numerical control of; of personnel of machine tool operation evaluate treatment precision; to examine the rationality that NC code; evaluates the machinability; of the product to evaluate procedure. CNC Milling